This invention relates to a looping apparatus capable of accumulating and paying out belt-like materials such as, for example, strips independently of a proceeding or subsequent processing step.
In order to continuously process a belt-like material to, for example, plate a soft steel strip, it is necessary that a means for temporarily storing the belt-like material be provided.
In general, in a so-called "looper" is employed, a storing means a belt-like material constituting a subsequent coil can be payed out while a belt-like material already payed out is temporarily stored in the storage means, to join by welding a front end of newly played out, belt-like material stored to a rear end of the stored belt-like material thereby enabling the belt-like materials to be continuously supplied to a processing machine in a subsequent step. A looper of a looping tower system, which is moved on a vertical frame, and a looper of a looping car system, which runs on horizontal rails, are widely used.
In, for example, U.S. Pat. No. 3,310,255, a spiral looper is proposed which is capable of storing a large quantity of a belt-like material, hereinafter referred to as a strip in a comparatively small space. In this proposed looping apparatus, a strip is vertically on a spiral looper, i.e. a strip supplied in a horizontal direction is twisted and put in a vertically extending state by a guide roller to be sent to a spiral looper. Thus, it is necessary that a strip in a horizontally extending state be twisted in a vertically extending state in a section including positions on the front and rear sides of the spiral looper. A disadvantage of this proposed looper resides in the fact that, due to the strip-twisting section, it is necessary to provide a comparatively large area which extends in longitudinal direction of a strip, thereby increasing the dimensions of a looping apparatus.
In such an apparatus, a strip is moved as it is wound in a plurality of layers, i.e. into a coil on an upper table or a lower table in a spiral looper, and a moving speed of the strip wound into a coil, i.e. a speed v of the portion of the strip which is halfway between upper and lower surfaces thereof does not vary in different points on the coil, for example, in points on inner and outer layers thereof. Accordingly, as shown in FIG. 1, which shows outer and inner strips 1, 1' contacting each other at their surfaces 1a,1a', a moving speed v' at the contact surface 1a of the outer strip 1 and a moving speed v" at the contact surface 1a' of the inner strip 1' can be expressed by the following equations: ##EQU1## where:
v equals a moving speed at a portion of a strip which is halfway between the upper and lower surfaces thereof;
h equals the thickness of a strip; and
R is a radius of the coil between the center thereof and the contact surfaces of the strips.
Therefore, a speed difference .DELTA.V=V"-V'=vh/R necessarily occurs on the contact surfaces 1a, 1a' of the strips 1, 1'. This necessarily causes slipping between the strips 1, 1', so that it is impossible to prevent the strips 1, 1' from being damaged. For these reasons, it is difficult to apply such a looping apparatus to cold-rolled strips, zinc-plated strips and color steel plates, which strictly require a high quality of surface.
An object of the present invention is to provide an apparatus for looping belt-like materials which presents an occurrence of slipping between layers of a strip wound into a coil, while the strip is moved.
In accordance with present invention, an apparatus for looping belt-like materials is proposed which includes first and second looping units for winding a moving strip, i.e. a moving belt-like material helically into first and second coils, a means for drawing out the portion of the belt-like material forming the first coil, into the second coil, with a plurality of support rollers being arranged annularly along each of the portions of the wound belt-like material which constitute the first and second coils. Frames are provided with the annularly arranged support rollers, and driving means apply the rotary force to the frames. Means are provided for displacing the support rollers in a radial direction of an imaginary circle, along which the rollers are arranged, in accordance with variations in the diameters of the coils so as to bring the support rollers into contact with the portions of the belt-like material which constitute the coils.